Improvement in elevators



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Improvement in E| evators..

Patented May 28 L.HATW00D.,

Improvement in. Ele- Patented May 28,1872;

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UNITED STATES PATENT FFICE.

LEONARD ATWOOD, OF NEW YORK, N. Y., ASSIGNOR TO GEORGE W. BROWN AND I. SHERBURN ATWOOD, OF SAME PLACE.

IMPROVEMENT lN ELEVATORS.

Specification forming part of Letters Patent No. 127,138, dated May 28 1872; antedated May 11, 1872.

To all whom it may concern:

Be it known that I, LEONARD Acrwoon, of the city and State of New York, have invented an Improvement in Elevators for Buildings, and the following is declared to be a correct description of the same.

Elevators for buildings have been made by a vertical screw-shaft at one side of the platform or car, said shaft running the entire length of the elevator; but great expense is involved in the construction of screws of this character, and many difficulties are experienced in mounting the same so that the car or platform will not tend to bend said screw.

My invention is made to lessen the cost of the screw, to support the same at suitable distance, and to relieve said screw of all lateral strain that otherwise would tend to bend the same.

I accomplish these objects by making use of a stationary case attached to and supported by the building or structure in which the elevator is applied. This case serves two purposes: first, of a slide for the car to keep it in position and to sustain the lateral strain or leverage of the car as it projects at one side of said case; and second, of a support for the screw-shaft and the screw-sections upon said shaft. The screw-sections act upon a rack that is attached to the car, and is of greater length than the distance from one screw-section to the next, so that one screw-section co1nmences to act upon the said rack before the other end of the said rack passes either above or below the adjacent screw-section, according to the direction in which the car is being moved. In consequence of employing screwsections instead of a continuous screw, the shaft of the screw can be supported by the case between such sections, and the screw and shaft can be much smaller than heretofore necessary.

In the drawing, Figure l is a vertical section of the case carrying the screw-sections; Fig. 2 is a horizontal section of the same; Fig.

3 is a vertical section illustrating the general features of the elevator as fitted into a buildthe case with the rack-bar in section.

In the building, the proper openings are left through the floors, and these should be inclosed, except where doors are provided, as shown at a a, and the car I) should be provided with a wire rope passing over a pulley, and counterpoised either by a weight or by a second car, that descends as the first car ascends, and the reverse.

The metallic case this made in suitable lengths, with flanges e, so that these lengths are bolted together. This case is to extend the length of the elevator, and supported by being built into the brick-work or by suitable supports or connections 6 to the building. The bar b is made with guides 'i i sliding upon the flanges 2 2 of this case at, or such guides might pass into the case, the flanges 2 2 being inward instead of outward; in either instance the case d has a vertical opening through its side the entire length, in which the rack-bar 1 slides, and this rack-bar is connected to the guides 'i 'i and to the car b. Within the case at there are journal-boxes m, at'suitable distances apart, that receive the vertical shaft 72, and upon this shaft are the screw-sections 0 0, placed at a distance apart less than the length of the rack-bar I, so that said rack-bar will always be in gear with one of the screws, and thereby the car will be either raised or lowered,

according to the direction of the revolution of the screw.

I prefer to make the shaft'n in lengths the tering the upper end of the shaft half-way through the said screw-section, and the lower end of the next length of shaft passing into said screw-section, the shafts are coupled together by the screw and I remark that keys may be used to connect the parts, or the shafts may be prismatic where the screws are applied.'

The means for rotating the shafts and screw sections may be of any desired character. I have shown a pulley, 1", and this is within the frame t, below the case d.

I claim as my invention=- A 1. A stationary case, forming slides for the guides '5 upon the car or platform, and receivbearings within the case, that is made in sec- 4 ing the screw for moving such car or platform, tions bolted together, substantially as set forth. Signed by me this 5th day of October, A.

substantially as set forth.

2. The case d, made of sections bolted to- D. 1871.

gether, and containing journal-boxes, in com- LEONARD ATWOOD. bination with the shaft n and screw-sections, 7 l substantially as set forth. Witnesses:

3. The screw-sections '0 0, forming couplings GEO. T. PINOKNEY, for the lengths of shafting n, and resting upon UHAs. H. SMITH. 

